Using a food processor is the fastest way to incorporate butter into dry ingredients. You can also do it by hand. You can either use a pastry cutter or 2 knives like our grandmothers might have done. First you cut the cold butter into small pieces. Then add your dry ingredients. Using the pastry cutter or knives cut the mixture into coarse crumbs. When it looks fairly uniform add your liquid ingredients. Be careful not to overwork. If you think the butter has gotten too warm, put the mixture in the refrigerator for 10 minutes before adding liquid.
